Ammonia → HCID 20337183, compound

A mixture of diethyl 5-(N-ethoxycarbonyl-N-ethoxycarbonyloxyamino)pentylphosphonate (90.0 g.) and conc. hydrochloric acid (630 ml.) was refluxed for 14 hours and concentrated under reduced pressure to give a residue, which was dissolved in water (200 ml.). The aqueous solution was washed with ethyl acetate, treated with activated charcoal and then concentrated under reduced pressure to give an oily residue (53.7 g.). The residue was dissolved in a mixture of water and methanol (1:2). The solution was adjusted to pH 4.0 with 28% aqueous ammonia under ice-cooling to give precipitates, which were separated by filtration, washed with methanol and dried to give crude crystals. The crystals were dissolved in 20-fold volume of water under heating, treated with activated charcoal and then cooled to ambient temperature. To the solution was added ethanol (100 ml.) and then allowed to stand overnight at 4° C. to give crystals, which were separated by filtration and dried to give crystalline 5-(N-hydroxyamino)-pentylphosphonic acid (18.8 g.). M.p. 184°-185.5° C. (dec.).

1. temperaturewas refluxed for 14 hours
2. concentrationconcentrated under reduced pressure
3. customto give a residue, which
4. washThe aqueous solution was washed with ethyl acetate
5. additiontreated with activated charcoal
6. concentrationconcentrated under reduced pressure
7. customto give an oily residue (53.7 g.)
8. temperaturecooling
9. customto give
10. customprecipitates
11. customwhich were separated by filtration
12. washwashed with methanol
13. customdried
14. customto give crude crystals
15. temperatureunder heating
16. customto give crystals, which
17. customwere separated by filtration
18. customdried

ORD record

ord-9145614ad7bd4ddf89b920244ec6f1d1

Source dataset

uspto-grants-1980_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04206156